Liquid-cooling apparatus



June 26, 1928. v

' H. c. KELLOGG LIQUID COOLING APPARATUS 2 Sheets-Sheet 1 Filed Sept, 12, 1927 June 26, 1928. H. c: KELLOGG LIQUID coomne APPARATUS Filed Sept. 12, 1927 2 Sheets-Sheet 2 Patented June 26, 1928..

. UNITED s'rATEs -PATENT- IOFFI'C1E,; v

HERBERT C. KELLOGG, OI DETROIT, MICHIGAN.

LIoum-cooLme APPARATUS.

.- Application filed September-12, 1927. Serial No. 218,890.

1 The invention relates to improved apparatus for the cooling of liquids and particularly for the cooling of. liquids sub ect-to variable or intermittent draft. The present application"c'iinstitutes a continuation in part of my application Serial No.- 745,162, filed October 22, 1924. Y 1

Some of the chief 'objectsof the invention are comprehended iii "the provision ofapparatus for the cooling of liquids subject to variable draft or having a variable heat con-' tent, characterized by (a) very high cooling efliciency, (b) large cooling capacit in proportion to the capacity of the refrigerating apparatus employed, (a) close automat c regulation of the temperature of thehquid drawn,"up to the maximum capacity ;of the apparatus, notwithstanding wide variations in the rate of draft or heat content. ofthe liquid, (d) a high degree of compactness for a given cooling capacity, (e) minimized heat absorption from the surrounding atmosphere, and (f) adaptability of a given size of the cooling apparatus proper toa rela;

.tively wide. range of cooling capacities. i A further object of the invention is the provision of a liquid cooling apparatus of the character above indicated which is especially adapted for the cooling and dispensing of carbonated beverages. v Other objects of the invention more orless ancillary or incidental to theforego' g, as

well'as the manner in'whichall of the vari-" ous objects are attained, will be apparent from the following description which sets forth in connectiOniwith the accompanying drawings one form .of preferred apparatussuitable for the practice of the invention.

In the drawingsz. r

Fig. i is a perspective view of an apparatus embodying myimprovements and which .isespecially adapted for the cooling and dispensingof beverages.

Fig. 2 is a central vertical section through the apparatus shown in-Fig. 1 with some of thefparts shown in elevation.

Fig. 3 is an enlarged central vertical section of the primary cooling unit of the appa-' ratus. p

Fig. 4 is a vertical sectional view of the thermostaticswitch with some of the parts shown in elevation.

Fig. 5 is a fragmentary elevation showing a modified form of the thermostatic control devices.

The apparatus comprises a 'cooling' unit suitable support. I

in which liquid refrigerant is vaporized and throu h which the liquid to be cooled asses in or er to give up its excess heat to t e refrigerant, and means for withdrawing the vaporized refrigerant from the cooling unitand again liquefyingit. Where, as in the case. of the apparatus illustrated, a carboIiated beverage is'to be cooled, I-prefer to also 1 provide .a -chamber in which the excess charging gas can be liberated beforethe beverage is. dispensed. This .latter. chamber may also perform the function of a secondary cooler, as will'later be explained."

Referring-indetail to the construction illustrated, '1 designates in its entirety the frameand casing structure. This structure is divided by a horizontal partition 2"into a lower section '3'. and an upper section 4.

The lower section. 3 .has a base or floor 5 which is provided with feet or-pedestals 6 adapted to rest. upon the floor or other Within the upper section 4 of the casing is dis osed a tank 7 adapted to hold abody of iquid'refri erant 8, such for example \as sulphur dioxide; and permit vaporization thereof when-the refrigerant absorbs heat. Refrigerant is withdrawn from the .tank 7 in vapor form and returned to it in liquid form by the refrigerant liquefying apparatus "9 which is housed in the lower part 3 of the casing. This refrigerant liquefyi g apparatus comprises a compressor10 riven by an electric motor 11 which drives the compressor through suitable gearing enclosed in casing 11, a condenser 12 in which the compressed gaseous refrigerant delivered. from the com ressor 10. is cooled and lique-. fied. Water or cooling the compressed gas 05 in the condenser 12 is supplied through the usual cooling coil (not shown) in the'condenser; The suction side of the compressor is connected by the pipe 15 with the vapor space'lfi above theliquid refrigerant '8. in the tank 7, the upper end of, the pipe15 being connected with. the upwardly inclined open-ended tube 15 within the tank 7. The condenser 12 delivergs the refrigerant lique fied therein into a sump or passage (not I shown) formed in the crankcase casting of the, compressor Y10 and connected with this sump is a pipe 17 which at its upper end connects with a 'valve 18 actuated by float 19 partially submerged. in the liquid refrigerant 8, this float valve serving to admit liquid refrigerant from the condenser and maintain it at a predetermined level in the tank 7.

I do not show and describe the motor driven compressor and condenser in detail, as any suitable form of refrigerant liquefying means adapted to be automaticaly started and stopped can be employed. It may be noted, however, that the motor driven commaticall 'pressor and condenser apparatus illustrated inthe drawing is one commercially well known at the time of the filing of my orignial application and reference may be made,

,15 for further details of its construction and operation to Letters Patent of the Republic of France No. 547.971, datedFebruary 27, 1922.

The operation of the compressor is autocontrolled by a thermostatic switch evice 20. A thermostatic bulb 21 which extends into the tank 7 and contacts with the liquid refrigerant therein cornmunicates through a capillar tube 22 with the switch device to actuate t e same by the expansion of a suitable liquid contained in the bulb and tube. Various expanslble liquids can be employed for this purpose, depending upon the character of the switch.

, With a suitable switch mercury, for exa cylinder 24 which encloses a verticall ed sleeve in the plate 24 it can be adjusted compressible and expansibleas tight be lows 25. This bellows at its ower end has a gas-tight connection with the lower end of the cylinder24. The capillar tube 22 communicates through the top 0 inder 24 with the interior space between the c linder and the bellows and the expansible thermostatic fluid fills thislatter space as well as the capillary tube and the bulb 21. The top plate or disc 25 of the/bellows 1s ri idly connected to a depending; lunger 26 w ich slidably engages a three ed sleeve 27 adjustabl' mounted in a bottom plate s24 of the cy inder. By turning the threadup and down and can be secured in adjusted position by lock nut 28. A member 29 resting upon the upper end of the sleeve 27 serves as "an abutment for the lower end of a compression spring 30 the upper end of which engages a flanged ring 31 slidably mOunted-"On'the plunger Obthe cylviously. adjustment of sleeve 27 varies the tension of the spring 30 thus varying the force with which the s ring is adapted to resist compression of t e bellows and restore the same to its expanded position. A light coil compression spring 32 at its upper end engages the recessed under side of the sleeve 27 and at its lower end engages adjustable abutment nuts 33 on the plunger -.on the floor of the casing 23 is of the snap or toggle type. This kind of switch iswell known and it will therefore suflice to state that the switch illustrated comprises a pair of fixed terminals or electrodes 35, 36 and a movable member or electrode 37 which is mounted on a: resilient lever 38 pivoted on st 39. The switch lever38 is actuated y a toggle spring 40 connected at one end 't-othe lever and at its other end with a depending link 41 which is connected to one end of an actuating lever 42 pivoted at its other endto' a vertically adjustable support 43. A second lever 44 is in turn pivoted at .45 to the lever 42 and also carries an abut-' ment pin 44 which engages an upward extension42 of the lever 42. The lever'44 also carries a flat spring 44Which is adapted at its freeend to be. enga ed by the lower end of the plunger 26 whic passes through an opening provided in the lever 44 for this purpose. A shoulder 26" on the plunger engages a member 44 on lever 44 to limit the exmg of the spring 44", while a collar 26 on the lower end of the plunger is adapted to engage th member 449 to elevate the lever 44 and with it the lever 42. When the bellows and the plunger 26 are depressed the levers 44 and 42 and the link 41 are moved downward and the switch closed, while upward movement of the same parts causes the switch to, open. 46 is a pivoted latch device whichengages the switch arm 38 ,to hold it in closed position until the link 41 has been raised nearly to its uppermost position whereupon the lever 47 is actuated by the link 41 to engage the latch 46 and disengage the same from the lever 38. the opening of the switch.'

It will now be seen that when the perature of the thermostatic-, fluid in the 'ulb 21 rises the resultant increase of its vapor pressure .will cause compression of the bellows device '25 with resultant closing This insures a sudden snap action for of the switch 34 and startingof the motor driven compressor; whereas the lowering of the temperature of the thermostatic fluid decreases its vapor tension and this permits the bellows 25 to expand under its inherent resiliency and that of the spring 30 with the result that the switch 34 is opened. It is obvious that a substantial movement of the bellows is necessary to actuate the toggle switch both in closing and opening and that this movement 1 corresponds to a certain range oftemperature change of the thermo-- static fluid. Bysuitable adjustment of the springs 30 and 32 the mean temperature of this temperature range referred to can be varied up and down and also the extent of the temperaturerange itself can be varied. This need not .be explained in further detail since this form of switch was well known at-the time 'of the filing of my original invention is not concerned with them.

- \Vithin the tank 7- and immersed in the liquid refrigerant therein is a metallic c011 48 which is connected at one end with an inlet pipe 49 for the liquid to be cooled and at its other end with a discharge pipe 50. The coil 48 is made of suitable dimensions as to cross-sectional capacity and length as will later be explained. The discharge pipe 50 may lead directly or indirectly to the means which control the flow of the liquid to be cooled. ,In the present case the apparatus is designed to cool a charged beverage and the, pipe 50 accordingly leads into a gas liberating tank 51 which is disposed above and rests upon the top of the refrigerant tank 7 inheat conducting relation therewith. The discharge end of the pipe 50 is controlled ,bya valve 52 actuated by a float 53, this float valve serving to maintain apredetermined level. ofthe-liquid in the tank 1 51. This liquid, having been cooled to the desired temperature in the-coil 48, is maintained at substantially the same temperature in the tank51 by reason of the fact thatthe bottom" of the tank-51 contactswith the top -of the tank 7 sothat the two tanks and their icontents aremaintainedat substantially the, same temperature, Draft faucets. 54 are connected by tubes 55 with the lower part of the tank--51 and. serve toidispense the, cooled liquid therefrom. ,The upper v part of the chamber in; the tank 51. is, connected;

by a pipe 56 withIT-the water. waste pipe .14 through apressure regulat ng valve,5 7;wh1ch pressure of the latter arises above a certain point, the pressure being indicated by a gauge at 58. The refrigerant tank 7 and the beverage tank 51 are completely surrounded by heat insulating packing 59 of cork or the like which is interposed between the tank and the walls of the casing structure. This packing minimizes absorption of heat from the surrounding atmos phere of both the tanks 7 and 51.

In the operation of my improved cooling apparatus, when intermittently the draft faucets 54 are opened for the dispensing of the beverage, the latter is drawn from the supply in the tank 51. This withdrawal of liquid from the tank 51 lowers the liquid level therein and thereupon the float valve 52 is opened to admit more liquid and restore the level in-the tank. Such additional liquid, entering through the inlet pipe 49 at a temperature above that to which it'is to be cooled, passes into the coil 48 which is immersed in the liquid refrigerant in the tank 7. Here the liquid to be cooled gives upits heat directly tothe metal wall of the tube and'the latter in turn delivers this heat to theliquid refrigerant surrounding it with the result that some of the liquid refriger- I ant in contact with the tube is vaporized and rises through the liquid refrigerant to the vapor space at-the top of the tank. As this action continues, more and more vapor accumulates in the top of tank 7 with increase of pressure, and the temperature of the liquid refrigerant correspondingly rises. As soon as the temperature rises to a certain predetermined point, however, the expansion of the fluid in the bulb 21 closes the in turn it passes thropgh the pipe 17 back to the tank 7 into which it is admitted by the float valve 18, 19. The withdrawal of the refrigerant vapor from the tank 7 by the compressor reduces the pressure in the tank and permits more rapid vaporization of the refrigerant as thelatter absorbs heat from the liquid in the cooling coil. The rapid vaporization continues until-the temperature of theliquid refrigerant in the 'tank 7 is lowered to a predetermined point whereupon the contractionof the thermostatic fluidin the bulb 21 results in the opening of, the motor switch: and 'the stopping of the .compressoiz i Thelength ofiti me during which thc com-l .pressor willremainin operation for 'an 1 onel closing 10f the ,motor switch depen upon. the rate, atwhich the beverage or liquid Ito belcooledjis' drawn through the coolingl'f permits escape oi th car ni g s whe he :0 e d se 4 12 t a eiitent i, t at is conveniently connecte liquid. I prefer to so proportion to each other the dimensions of the cooling coil, i. e. its cross sectional capacity and its length, the maximum rate of draft of the liquid to be cooled, and the capacity of the refrigerant liquefying apparatus for. removing vaporized refri erant from the tank 7 ,that within the limits of variations of temperature of the liquid to be cooled, the refrigerant liquefying apparatus when in full operation will remove refrigerant vapor from the cooling tank or vaporizer as rapidly as said vapor is formed and that the exit temperature of the liquid cooled will not vary substantially from the temperature of the liquid refrigerant in the vaporizer. With such a relationship established, the apparatus has very remarkable capacity, efliciency and temperature regulating characteristics which I believe have never before been attained. 1

In Fig. 5 of the drawing I have shown a modified form of the thermostatic control. Here, the capillary tube connected with the thermostatic switch, instead of leading to a bulb immersed in the liquid refrigerant, leads into the low pressure or suction side of the refrigerant system. In the modified construction illustrated, 20 is the thermostatic switch, 22 is the ca illary tube and it to communicate with the suction pipe 15 which connects the vapor space of the vaporizer tank 7 to the suction inlet of the compressor. With this construction the bellows device which actuates the thermostatic switch is subject to and stop thecompressor to maintain" the temperature of the liquid refrigerant within the desired range. Consequently with this modified control the cycle of operation is the same as above described.

In order that the nature of my improvements may be understood as clearly as pos sible I will here give data by way of example for a characteristic embodiment of the invention in a cooler-for drinking-water. Let it be assumed that the cooler is to supply drinking water for steel mill workers and that it is 'desired to maintain the. temperature of the water as near 50 Flas possible. this temperature being recognized as mately 200 pounds of water to be cooled per hour or an absorption of 6000 B. t. u. per

per hour at various suction temperatures:

30 5500 B. t. u. 40 6900 B. t. u. 50 "8500 B. t. u.

For this capacity of cooler it has been found that a coil of nickel tubin of 3 outside diameter with 0.035 thick wall '1 having a submerged length of 36 feet will transmit the heat from the water to be cooled to the refrigerant at the rate of 8500 B. t. 11. per hour. The thermostatic switch of the compressor will be set to cut out at 47F. and to cut in at 53 F., thus limiting variation of the exit water temperature to 3 degrees from the desired temperature of 50 degrees.

An operating cycle of this typical cooler is as follows: The compressor having been automatically stopped at the minimum temperature of 47 F., of the liquid refrigerant or coohngcoil, water is now drawn through the cooler, entering at F. The temperature of the coil is raised, resulting in a rise of the liquid refrigerant temperature, with resulting vaporization of the'liquid refrigerant in contact with the coil. The coil is constantl maintained at approximately the liquid re rigerant temperature and the temperature of both continues to rise until 53 F. is reached when the thermostatic switch is closed and the compressor started. Refrigerant vapor is now withdrawn from the vaporizer and condensed by the com ressor at its rated capacity, the cooling e ect of the resultingrapid vaporization preventing further rise of the liquid refrigerant temperature. If the rate of draft of water is at the maximum capacity of the compressor employed, the compressor will continue to run until the draft is lessened or stopped,

whereupon the temperature of the 11 uid refrigerant and coil will be lowered rapidly to the cutout temperature, namely 47 F., at which point the thermostatic switch is opened and the compressor stopped. This cycle will be repeated whenever sufficient heat is carried to the evaporator tank to raise the liquid refrigerant again to the out in temperature of 53 F. 4

In the above example, for the sake of definiteness, a temperature of 80 F. is assumed for the water entering the cooler, but under some conditions the temperature and heat content of the water to be cooled may vary ,peratures. Y

F., for example, is relatively high in considerably in the case'of drinking water and this, as well as the rate of draft, will affect the frequency and lengthof operation of the refrigerant liquefying apparatus. Furthermore, in some cases of liquid cooling to which the invention is applicable the variation of the temperature and heat content of the entering liquid, rather than the rate of draft of the liquid, may constitute the major variable'factor or even the sole variable factor. However, in. all cases of variable duty, the heat content of the liquid to be cooled per unit of time varies, and whether this latter variation be 'due' to variable rate of draft or variable entering temperatureof the liquid to be cooled, or to both of these, my improved apparatus automatically takes care of the variation.

My improved cooling apparatus has cer tain' notable advantages over any prior liquid cooling apparatus known to men advantage is that as the rate of draft or the heat content of the liquid to be cooled varies, the amount of heat removed by the refrigerant varies in the same proportion and consequently the temperatures both of the liquid refrigerant and of the liquid drawn are constantly kept within the narrow range between the cut in and cut out tem- The exit water temperature of comparison with the refrigerant tempera tures in liquid cooling systems in which ice is formed and the water or beverage is cooled by the ice. By keeping the liquid refri erant temperature at the relatively hig value indicated the compressor operates at close to maximum capacity in terms of mass of vapor handled and at very'high efliciency in terms of B. t. u. handled per unit power consumption.

A further advantageprelated to that last referred to, is that the heat absorption from the surrounding atmosphere is minimized because the liquid refrigerant and the metal parts are maintained at the (relatively high) temperature of the cooled liquid, say 50 F., whereas in ice maintaining coolers the cooling bath and metal parts of the apparatus are maintained at a temperature of approximately 32 F. 5 Both of the advantages-last referred to above are. of course, dependent upon the maintenance of the previously described relation between the cooling tube Tonconduit, the maximum rate of draft of the liquid cooled and the maximum capacity. of the compressor, together with the automatic control of the operation of the compressor.

Still another advantage is found in the extremely high efliciency of the relatively direct heat interchange between the liquid to be cooled and the liquid refrigerant, the two liquids being separated only by the one thin metal wall so that heat is conducted rapidly One with small temperature head and there is' no reduction in the rate of heat transfer due i i to convection circulation such as occurs when a cooling bath of water, brine or the like surrounds the conduit or container of the liquid to .be cooled.

- Again, by reason of the extremelyhigh highly eflicient heat interchange gives rapid z I cooling so that it is not necessar to maintain any considerable body of 000 ed liquid to meet prolonged drafts thereof. Both of these circumstances favor compactness and the cooling unitgof my apparatus is in fact exceedingly compact, cooling capacity considered. By coolin unit it'willbe under-. stood that I meant at part of the refrigerant circuit and ,that part of the circuit of the liquid to be cooled which are in'heat interchangingrelation to each other. In the particular construction illustrated the cooling unit consists of the-tanks 7 and 51 and their working parts, the tank 7 and its parts forming what may be termed a primary cooling unit while the tank 51; and its parts may be considered a secondary cooling unit. Of course, if-the dispensing faucets are connected directly to pipe 50, the tank 7 and its parts compose the cooling unit.

compactness of the primary cooling unit. That is to say, this cooling unit for even relatively large capacities can be kept with- A still further advantage flows from the a in such limited bounds that the element of space is-not: a controlling factor and it is entirely feasible to use the same cooling unit i for a considerable range of capacities and large scale production at low cost is thus favored. 1 a

Again, my cooler presents the marked ad- 7 vantage of uniformly close-regulation of the exit water temperature, and this advantage arises from the combined, results of (a) properly relating the cooling coil and the capacity of the refrigerant liquefying means in relation to each other and to the maxia 'mum draft and heat .content of the liquid to be cooled, (b) rapid heat interchange, (c) automatic starting and stopping of the refrigerant liquefying means, and (d) the directing of the li aid to be cooled in a defi nite path througi the cooling unit, so that liquid entering the unit at high temperature cannot possibly mingle with low tempera-' ture liquid being withdrawn.

It is to be. observed that 1n the case of the form of, apparatus illustrated, advantage may be taken of the upper tank not only to.

relieve excess gas pressure but-also .to perform anadditional function which in some instances maybe of considerable value. As ha been pointed out, the upper 5 1 is i 0 7 so that the liquid in the upper tank is mainwhich it is desired to maintain.

tained at substantially the same temperature as that of the liquid refrigerant in the lower tank or cooling unit. For this reason it is possible for given service conditions to use cooling apparatus of somewhat smaller capacity than would otherwise be possible withoutseriously interfering with'the close temperature regulation of the-dispensed liquid Thus the cooling unit and refrigerant liquefying means may have asomewhat smaller capacity than would otherwise be provided to take care of the extreme peak load on the cooler, because when the relatively infrequent peak load occurs even if the liquid is not reduced quite to the desired "and redetermined temperature range in the primary cooling unit, since this liquid is delivered into a substantial mass of liquid in the upper tank which is at a temperature within the redetermined range, the liquid drawn from -t e upper tank undersuch conditions will vary but slightly from the predetermined temperature range and decidedly lessthan it would vary if under the same conditions the draft were made direct from the coil of the cooling unit. Obviously this feature can be taken advan tage of whether the liquid being cooled iscarbonated or not.

The essential thing so far as this feature is concerned, is the rovision of the supplemental reservoir into which the liquid is discharged after: assifig through the cooling conduit'and whic holds said'liquid in such relation to the refrigerant that the latter keeps the liquid'i-n the reservoir substantially at the temperature of the refrigerant.

From what has been said in connection with the advantages above enumerated, it will be clear thata number of the ftatures of the apparatus are peculiarly interdepend ent. For exam le, the provision of the refrigerant lique ying means of sufiiciently large capacity to take care of the cooling of the liquid substantially as rapidly as it may flow is necessitated by the nature of the heat interchange devices employed. In liquid cooling systems heretofore used in practice, the capacity of the refrigerant liquef ing t o the liquid cooled are much less' interdependent and .their relation to each other is much less important than in the case of applicants aparatus, because in the prior systems, it has n customary to hold considerable bodies of cooled liquid and in some instances of ice' as well, to take care of peak loads. In applicants primary cooler system, "on the other hand, the. provision of the refrigerant liquefying means with capacity of the character specified is essential to secure therapid heat interchange that is-eflect'ed between the liquid to be cooled and the. refrigerant when rate necessary to maintain the operation ofthe cooling unit at maximum capacity. The

provision of the refrigerant liquefying meanswith automatic control and of the suitable capacity specified in combination with the direct heat interchange type of cooling means produces an apparatus that is extremely flexible in its adaptability to widely varying loads. In this connection it is to be observed that the refrigerant liquefying means is kept in operation a smaller proportion of the time due to the rapid rate of cooling, thus mini-' mizing wear in the caseof the compressor type of liquefier.

While I have shown a specific form and type of apparatus for the purpose of explaining and illustratingthe invention, it will be understood that the construction of the ap pa-ratus can be varied widely without departing from the invention. Obviouslly use can be made of any form of refrigerant quefying means adapted to withdraw the refrigerant va or from the cooling unit at a suit-able rate an have its 0 eration automatically controlled. And .in t e case of the primary cooling unit itself, while I prefer to maintain therein a definite mass of liquid refrigerant and to pass the liquid to be cooled through a conduit immersed in the liquid refrigerant, it will be understood that the 'means for admitting the refrigerant into the cooler may be any sort of cont-rolling means that will automatically admit more or less of the refrigerant in liquid form, the advantages of my invention being attained to at least some degree if there is provided a conduit for the liquid to be cooled adapted to cause the flow of said liquid in a definite path throughthe cooling unit together with a vaporizing chamber directly associated with the said conduit and containing in operation liquid refrigerant in direct heat interchange relation with a wall of the said conduit and the liquid to be cooled on the other side of said wa'll. Again, it is quite obvious that the means employed for automatically controlling therefrigerant liquef'ying means may be any form of thermostaticor thermot.

pressure device responsive to change of the temperature of the liquid refrigerant ,in the coolin unit.

Sim1larly,-while I have shown the invention as embodied in cooling apparatus for dispensing charged beverages, it is obvious from what has been said in the description of the apparatus that theinvention is a plicable toa great variety of uses such, or ex ample, as the cooling of drinking water on draft, the cooling of water and beverages dispensed from soda fountains, and in fact the cooling of any flowing liquid having a variable or intermittent flow or a variable tion system including means for liquefying refrigerant .vapor and a vaporizer chamber adapted to receive the liquefied refrigerant;

a conduit for the liquid to be cooled com prising a metal section having its ivall in contact on one side with the liquid refrigerant in the vaporizer; draft means associated with the conduit by which the liquid to be cooled is subject to draft intermittently at variable rates; and means operating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to vary the operation ofthe refrigerant in liquefying means. and thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range; the said section of the conduit being proportioned to direct the liquid to be cooled in a pre-v determined path and the said section of conduit, the maximum rate of draft of the liquid to be cooled and the maximum capacity of the refrigerantliquefying means to remove refrigerant vapor from the vaporizer chamber per unit of time being relatively proportioned to insure contact of the liquid drawn with the other side of the wall of said conduit section for a time suflicient to insure that substantially all of the sensible heat of the liquid to be cooled'in excess of that corresponding to the maximum temperature of the said predetermined range shallbe conducted from the liquid drawn directly through the wall of said conduit section to the refrigerant during thepassage of the liquid through said conduit section.

2. In apparatus for cooling liquids on draft, the combination of aclosedrefrigeration system including a means for liquefying refrigerant vapor, a vaporizer chamber, and means operating in conjunction with the refrigerant liquefying means for automatically maintaining a body of liquid refrigerant in said chamber; a conduit for the liquid to be cooled comprising a metal section im v mersed in the said body of liquid refrigerant; draft means associated with the conduit by which the liquid to be cooledis subject to draft intermittently at variable rates; and means operating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to stop and start the refrigerant liquefying means and thereby maintain the temperature of-the' said liquid refrigerant within a'limited predeterm ned ant liquefying means to remove refrigerant vapor from, the vaporizer per unit of timebeing relatively proportioned to'insurecontact of the liquid to'be cooled with the inner surface of said conduit section for a time sufficient to insure that substantially all of thesensible heat of the liquid to be cooled in excess of that corresponding tothe maximum temperature of the said predetermined range shall be conducted from the said liquid directly throughxthe wall of said conduit section to the refrigerant during the passage of the liquid through said conduit section.

3. In apparatus for cooling liquids on draft, the combination of a closed refrigeration system including 'a motor driven com pressor, a cdndenser, a vaporizer chamber, and means operating in conjunction with the compressor and condenser for automatically maintaining a body of liquid refrigerant in said chamber; a'conduit for the liquid to be cooled comprising a metal section immersed in the said body of liquid refrigerant; draft means associated with the conduit by which the liquidto be cooled is subject to draft intermittently at variable rates; and means operating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to stop' and start the compressor and thereby. maintain the temv perature of the said liquid refrigerant within alimited predetermined range; the said immersed section ofthe conduit being pro- *portioned to direct the liquid to be cooled in a predetermined vpath and the said immersed section of, conduit, the maximum rate of draft of the liquid to be cooled and the maximum capacity of the compressor to remove refrigerant vapor from the vaporizer cham ber per unit of time being relatively proportioned to insure contact of the liquid to be cooledwith the inner surface of said conduit section for a time suflicient to insure that substantially all of the sensible heat of the liquid to be cooled in excess of that corresponding to the maximum temperature of the said predetermined range shall be conducted from the said liquid directly through the wall of said conduit section to the refrigcrant during the passage of the hquid through said'conduit section.

4;. In apparatus for cooling liquids on contact on one side with the liquid refrigerant in the vaporizer; a reservoir for liquid to be cooled into which the said metal conduit section delivers liquid that has passed thercthrough, the liquid in the reservoir being maintained in heat interchanging relation with the liquid refrigerant 1n the vaporizer chamber; draft means by which the cooled liquid in the reservoir is subject to draft intermittently at variable rates; and means operating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to vary the operationof the refrigerant liquefying means and thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range"; the said section of the conduit being proportioned.

to direct the liquid to be cooledin a predetermined path and the said section of'conduit,' the maximum rate of draft of" the liquid to be cooled and the maximum capacityof the refrigerant liquefying means to remove refrigerant vapor from the vaporizer chamber per unit of time being relatively proportioned to insure contact of the liquid drawn with the other side of the wall of said conduit section for a'time suflicient to insure that substantially all of the sensible heat of the liquid to be cooled in excess of that corresponding to thefmaximum tem perature ofthe said predetermined range shall be conducted from the liquid drawn to be cooled comprising a metal section hav-' ing its wall in contaction one side with the liquid refrigerant in the vaporizer, said section of conduit being adapted to direct the liquidto be cooled in a predetermined path; a metal walled reservoir for liquid to be cooled into which the said metal conduit section delivers liquid that has passed therethrough; the walls of the reservoir and vaporizer being joined together to form a metallic heat flow path through both of said walls between the liquid in the reservoir and the liquefied refrigerant in the vaporizer; draft means by which the cooled liquid in the reservoir is subject to draft in termittently at variable rates; and means operating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to vary the operation of the refrigerant liquefying means and thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range.

adapted to receive the liquefied refrigerant;

6. In apparatus for cooling carbonated it beverages on draft, the combination of a closed refrigeration system including means for liquefymg refrigerant vapor and a vaporizer chamber adapted to receive the liquefied :refrigerant;a conduit for the carbonated liquid to be cooled comprising a metal section having its wall in contact on one side with the liquid refrigerant in the vaporizer; a reservoir for the carbonated liquid into which the said metal conduit section delivers liquid that has passed therethrough, the liquid in the reservoir being maintained in heatinterchangingv relation with the liquid refrigerant 1n the vaporizer chamber; automatic means for admitting the carbonated beverage into the said reservoir so as to maintain it at a predetermined level therein; means communicating with thespace above the said liquid level for exhausting the charging gas above a predetermined pressure; draft means b which the cooled liquid in the; reseirvoir 1s subject to draft intermittently at variable rates; and means operating automatically with change .of temperature of the liquid refrigerant in the vaporizer chamber to vary the operation of the refrigerant liquefying means and thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range; the said section of the conduit being proportioned to direct the carbonated liquid to be cooled in a. predetermined path and the said section of conduit, themaximum rate of draft of the liquid to be cooled and the maximum capactiy of the refrigerant liquefying means to remove refrigerant vapor from the vaporizer chamberper unit of time being relatively proportioned to insure contact of the liquid drawn with the other side of the wall of said conduit section for a time sufiicient to, insure that substantially all of the sensible heat of I the liquid to be cooled in excess of that corresponding to the maximum temperature of 11 the said predetermined range. shall be conducted from the liquid drawn directly through the wall of said conduit section to the refrigerant during the passage of the liquid through said conduit section.

7. In apparatus for cooling flowing liquids, the combination of a closed refrigeration system including'means for lique'fying refrigerant vapor and a vaporizer chamber a conduit for the liquid to be cooled comprising a metal section having its wall in contact on one side with the liquid refrigerant in the vaporizer; means associated with the conduit causing variation of the heat content of the liquid entering said metal section of the conduit per unit of time; and meansoperating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to 150 vary the operation of the refrigerant-liq 1 9."In' apparatus for. cooling flowing liquefying means and thereby maintain the.

temperature of the said li uid refrigerant within a limited predetermined range; the

said section of the conduit being proportioned to direct the liquid to be cooled in a predetermined path and the said section of conduit; the maximum heat content to be removed from said liquid per unit of time and the maximum capacityof the refrigerant liquefyin'g means to remove refrigerant vapor from the vaporizer chamber per unit of time being relatively propontioned to insurecontact of the flowing liquid with the other side of the wall of}said conduit section for a time sufficient to insure that substantially all of the sensible heat of the liquid to be cooled'in excess of that corresponding to the maximum temperature of the said predetermined range shall be conducted from the liquid tobe cooled directly through the wallof said conduit section to the refrigerant during the passage of the liquid through said conduit section.

8. In apparatusfor cooling flowing liquids, thevcombination of a closed refrigeration system including a means for liquefying refrigerant vapor, a vaporlzer chamber,

and means operating in con unction with the refrigerant' liquefying means for. automatically maintaining a body of liquid refrigerant in said chamber; a conduit for the liquid to be cooled, comprising a m tal section immersed in the said body 0 liquid refrigerant; means associated with the conduit causing variation of the heat content of the liquid entering said metal sectlon of the conduit per" unit of time; and means operatingautomatically with change of tem-' perature of the liquid refrigerant in the va orizer chamber to stop and start the from the va orizer chamber per unit of in excess of that correspon re rigerant liquefying means and thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range; the said immersed section of the conduit being proportioned to direct the liquid to be cooled in a predetermined path and the said immersed section of conduit, the maximum heatcontent to be removed from said liquid per unit of time and the maximum capacity of the refrigerant liq uefying means to remove refrigerant vapor time be' re atively. proportioned to insure contact 0 'theflowing liquid with the inner surface of said conduit section for a' time sufiicient to insure that substantially all of the sensible heat of the li uid 'tobe cooled g to the mainmum temperature of the said predetermined range shall be conducted from the liquid be cooled directly through the wall of said .conduit section to the refrigerant during the passage of the liquid through said conduit section. v 1

liquid refrigerant within a ted termined range; the said eectionof the coumatically maintaining a body of liquid refrigerant in said chamber; a conduit for the liquid to be cooled comprising ametal j section immersed in the said. body of liquid refrigerant; means, associated with the con- I duit causing variation of the liquid entering the said metal section of the conduit per unit of time and means operating automatically with change of temperature ofthe liquid refrigerant in the vaporizer chamber to stop and start the compressor and thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range; the said immersed section of the conduit beingproportioned to direct the liquid to be. cooled in'a predetermined path and the said immersed section of conduit,

themaximum heat content to be removed from said liquid per unit of time and the -I naximum capacity of the refrigerant liq-- uefying meansto remove refrigerant vapor from the vaporizer chamber per unit of time being relatively proportioned to insure contact of the flowing liquid with the inner surface of said conduit section for a time sufficient to insure that substantially all of the sensible heat of the liquid to be cooled in excess of that corresponding to the. maximum temperature of the said predetermined range shall be conducted from the liquid to be cooled directly through the wall of said conduit section to the refrigerant during thepassage of the liquid through said conduit section.

- 10.;In apparatus for cooling flowing liquids, the combination of a closed refrlgerationsystem including means for liquefying refrigerant vapor and a vaporizer chamber adapted to receive the liquefied refrigerant; a conduit for the liquid to be cooled comprising a metal section having its wall' in contact at one side'with the liquid refrigerant in the vaporizer; a reservoir for liquid to 'be cooled into which the said metal con duit section delivers liquid thathas passed therethrough, the liquid in thereservoir bei ing maintained in heat interchanging rela-.

tion with the liquid refrigerant in the vaporizer chamber; vmeans associated with the f conduit causing variation of the heat "content of the liquid enteringsaid metal sec" tion of the conduit per unit of time; and means operating automaticallyv with change of temperature of the liquid refrigerant 1n the vaporizer chamber to vary the operation of the refrigerant liquefying means and thereby maintain the temperatur of the saidpredeconduit section for a time suflicient to insure that substantially all of the sensible heat of the liquid to be cooled inexcess of that corresponding to the maximum temperature of the said predetermined range shall be'conducted from the liquid to be cooled directly through the wall of said conduit section to the refrigerant during the passage of the liquid through said conduit section.

11. In apparatus. for cooling flowing liq uids, the combination'of a closed refri eration system including means for H uel ying refrigerant vapor and a metal wa ed vaporizer chamber adapted to receive the li uefied refrigerant; .a conduit for the liqui to be cooled comprising a metalsection having itswall in contact on one side with theliquid refrigerant in the va orizer, said section of conduit being adapte to direct the liquid to be cooled in a predetermined path; a metal walled reservoir and vaporizer for liquid to be cooled into which the said metal conduit section delivers liquid that has passed therethrough; the walls of the vaporizer and reservoir being joined together to form a metallic heat flow paththrough both of said walls between the liquid in the reservoir and the liquefied refrigerant inthe vaporizer;

means associated with the conduit causin variation of the heat content of the liqui entering said metal section of conduit per unit oftime; and means operating automatically with change of temperature of the liquid refrigerant in the vaporizer chamber to vary the operation of the refrigerant liquefying means and-thereby maintain the temperature of the said liquid refrigerant within a limited predetermined range.

. In testimony whereof, I hereunto aflix my signature.

HERBERT 0. 

